Re: Calculate a quotient for a count of boolean values (true or false)

Because you're calculating a - (b/c) instead of (a-b)/c

On 11 June 2013 11:51, Alexander Farber <alexander(dot)farber(at)gmail(dot)com> wrote:

> Hello!
>
> In a PostgreSQL 8.4.13 why doesn't this please
> deliver a floating value (a quotient between 0 and 1):
>
> select
> id,
> count(nullif(nice, false)) - count(nullif(nice, true)) /
> count(nice) as rating
> from pref_rep where nice is not null
> group by id
> ;
> id | rating
> -------------------------+--------
> DE10072 | -1
> DE10086 | 18
> DE10087 | 1
> DE10088 | -1
> DE10095 | 276
> DE10097 | 37
> DE10105 | 5
>
> I am trying to calculate a sum of ratings
> given by users to each other
> to draw a pie chart in a game, more details here:
>
>
> http://stackoverflow.com/questions/17040692/calculate-a-quotient-in-one-table-and-store-it-in-another-table
>
> Thank you
>
>
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